Grinding apparatus



March 16, 1948. w, o, DENNiS GRINDING APPARATUS Filed June 13, 1947 2 Sheets-Sheet 1 JNVENZ'ORE WILL/AM 0. DEN/W5 March 16, 1948. w. o. DENNIS GRINDING APFARATUS 2 Sheets-Sheet 2 Filed June 13, 1947 IN V EN T 0R. 0. DEN/W5 WILL/AM f/M/i @M Patented Mar. 16, 1948 entree STATESW PATENT OFFICE GRINDING APPARATUS William 0. Dennis, San Dimas, Calif. Application June 13, 1947, Serial No. 754,339

16 Claims.

This invention relates to the art of grinding, polishing, buffing and the like and more particularly to an apparatus which provides a plurality of grinding elements of different character within a single unit so that an operator may quickly and simply select the particular type of grinding Wheel adapted to his needs.

Buffing, polishing and the like are in essence modified forms of grinding and are therefore included in the term grinding throughout the present specification and claims. Thus reference to grinding wheel or grinding elements is intended to include all different types of grinding, wire, bufiing and polishing wheels inasmuch as the operation of the apparatus of the invention is independent of the particular type of grinding means employed.

Conventional practice under circumstances where a plurality of different grinding operations are required is to mount the necessary number of grinding elements on a single shaft in longitudinal relationship to each other and to provide power means for rotating the shaft. Such type of assembly not only involves a waste of space but also normally necessitates the provision of sufiicient power to drive all of the grinding elements simultaneously although only a small portion of these elements are in actual use.

The present invention is directed to overcoming these and other objectionable features in 7 conventional grinding apparatus by the provision of a device adapted to support a plurality of grinding wheels within the reach of a single operator and operable to select the desired wheel or wheels to be brought into power relation with the single drive means.

The above contemplated and other objects are accomplished according to the invention by the provision of an apparatus comprising a rotatable reel mounted on a suitable framework and provided with a plurality of spaced rotatable shafts upon the end of which are mounted a plurality of grinding elements. Power means, is provided in such operative relationship to the reel that different ones of the shafts can be engaged in powered relation thereto by suitable rotation of the reel. When one of the shafts is in such power relationship to the power means the remaining shafts are inoperative and are remote from the working zone so as not to interfere with the operations being performed on the rotating grinding elements.

In the preferred embodiment of the invention, the drive means is mounted within a pivotable housing whereby it may be pivoted away from the reel to permit the rotation of the latter to bring a second shaft in operating position. In this preferred form, when a proper shaft is in operation position, the housing is pivoted back toward the reel, thereby engaging the shaft and the drive means. 7 These and other features of the invention will be moreclearly understood from the following detailed description thereof taken in conjunction with the accompanying drawings in which:

Fig. 1 is a side elevation of the apparatus in operating position;

Fig. 2 is a front elevation apparatus of Fig. 1;

Fig. 3 is a detailed end view of the means of locking the drive means in power relationship to one of the shafts;

Fig. 4 is an end view of the apparatus of Fig. 1 as appearing when the drive means is disengaged from any of the grinding elements; and

Fig. 5 is a section view taken on the line 55 of Fig. 4.

Referring to Figs. 1 and 2 the apparatus comprises the framework I 0, which may be a conventional A frame as shown, upon which is mounted the reel l2 rotatable on the shaft [3 which is journaled in the journal boxes l4 and i5 mounted to the framework I0.

Mounted on the reel I 2 in rotatable relationship are the equally spaced shafts I8, [9, 20 and 2|. These shafts are journaled through bosses formed on the end members |2a and lZb of the reel I2. For example the shaft is is journaled through the bosses 22 on the member |2a and 23 onthe member 12b. The other shafts I 9, 20 and 2| are similarly journaled through bosses of like character. As shown in Fig. 2 in shafts l8 and 20, each of the shafts is threaded at both ends to receive a grinding wheel such as the grinding wheels 24, 25, 26, 21 and 28 shown in Fig. 1. Within the confines of the reel l2 each of the shafts is provided with a pulley member rigidly aflixed thereto which furnishes means, as hereinafter described to engage the shaft and the power means in operative relationship. Thus as shown in Fig. 1 and in Fig. 2 the shaft [8 is provided with a pulley 30 the shaft l9 with a pulley 3| and the shaft 20 with a pulley 32. The shaft 2| is provided with a similar pulley not visible in Figs. 1 and 2.

The drive means, shown in Fig. 1 in operative relationship with the shaft i9, is enclosed within a housing 34 and comprises the motor 35 provided with a pulley 36 connected by means of the belt 38 to, an idler pulley 39 mounted on a of a portion of the relation to the r shaft 40 in the upper part of the housing 34. For reasons hereinafter described the housing 34 is pivotably mounted to the framework It! at the point 42.

In Fig. 1 the power means is shown in operative relationship with the shaft l9 and is locked therein by locking means shown in Figs. 3 and 5. Each of the end members He and l2b of the reel l2 are provided with slots such as the slots 44, 46 and 41 projecting inwardly from the pe-; riphery of the member and providing 'nieans whereby a tool holder, such as the tool holder 48, may be mounted when the corresponding shaft is in operative relationship with the power means. Similarly each of the end members of the reel I2 is provided with four holes cut therein such as the holes 50 and shown in Fig. v1 to which a protective cowling such as the cowlings 53 and 54 may be affixed so as to form a guard over the particular grinding elements which are in use. The end members of the reel [2, may be webbed as shown in Fig. 1 to increase the mechanical strength thereof. Thus the end member I2a is shown provided with the radial webs 56 and 51.

Means are provided as a part of the housing 34 to lock the same in operative engagement with the particular shaft which is positioned so as to be so engaged. These means comprise the locking arms 60 and BI (Figs. 2, 3 and 5)-pivotab1y mounted to the housing 34 on the opposite ends of a rotatable shaft 64 mounted on the housing by brackets such as the bracket 61 (shown in Fig. 3). In Fig. 2 the housing 34 is narrower than the reel I2 to permit. the belt 38 to be brought into engagement with the pulleys 29. 30, 3| and 32, And for this reason the locking arms 60 and SI are offset as shown in Fig. 2 and are curved so as to engage the bosses through which the particular shaft is journaled. At the same time that the locking arms 60, 6| are engaging the bosses such as for example the bosses 68 and 69 (shown in Fig. 2) through which the shaft 19 is journaled. The axle 64 upon which the locking arms 60 and BI are mounted is locked within the end members of the reel 12. Thus as shown in Fig. 1 the end member. l2a and in similar manner the opposite end member 12b ofthe reel I2 is provided with the notches 12,13, I4 and 15 in its outer periphery. These notches have comparatively narrow outer openings and increase in size at their inner end. The shaft 64 is square broached at both ends thereof so that the ends may slip edgewise into the particular notches in the end members of the reel l2. When the shaft 64 is turned through a 90 angle the-face of the square broached ends prevents retraction from the notches. The locking arms fill-and 6| are in such relationship to the square broached end of the shaft 54 that when'the arms 60 and BI are in locked engagement'with the bosses such as the bosses 68' and 69, the shaft is also locked within the notches of the end members of the reel. The locking mechanism is provided with an actuating arm 18 whereby the locking arms 60 and GI may be disengaged'from the bosses and the broached ends of the shaft 84 may be at the same time rotated to permit retraction from the notches in'the reel. The operation of the locking device is more clearly portrayed in Fig. 5 which is a section view on the line 5-5'of Fig. 4. As shown in Fig. 5 the locking shaft 64 is rotatably mounted to the brackets 66 and 81 which project from the sides of the housing 34. Mounted onthe ends of the shaft 64 are the locking arms 60' and SI which,

as aforementioned, are offset so as to permit engagement thereof with the bosses formed on the outside of the reel. The shaft 64 is spring loaded by means of the helical spring which is aflixed at one end of the bracket 66 and at the opposite end to a collar 82 afiiXed to the shaft 64. The spring is so adjusted as to hold the locking device in the locking position. The lever 18 is likewise mounted to the shaft 64 and is employed to unlock the locking device against the force of the helical spring 80.

When the locking device is unlocked the housing 64 may be pivoted about its mounting 42 and retracted from the reel 2. The apparatus is shown in this position in the sectional elevation view of Fig. 4. In this position the reel 12 may be rotated so as to remove the shaft H from the operating position and to bring the shaft l8 into such engageable position. When the reel is rotated suificiently to bring the shaft 18 into the proper position for engagement with the power means the housing 34 may be pivoted towards the reel l2 and be locked in engagement therewith in the manner hereinbefore described so that the shaft l8 may be rotated by the contact of the belt 38 with the pulley 39 mounted on the shaft l8.

Because of the fact that one side of the belt 38 runs on the drive pulley 38 and the idler pulley 39 while the opposite side runs on the respective pulley mounted on the shafts l8, I9, 20 and 2|. the preferred type of belt to use for this purpose to obtain the greatest efficiency is the double-A typebelt as shown in Fig. 5. The relationship of the belt.38, the drive pulley 36 and a pulley such as the pulley 3i mounted on the shaft I9 is shown in Fig. 1.

It is apparent that many modifications in the apparatus of the invention may be incorporated without departure from the scope of the invention. Thus it is not essential that there be four rotatable shafts mounted to the reel [2 as a greater or lesser number is equally operative dependent upon the size of the reel employed. Further it is not necessary that a grinding wheel be mounted on both ends of each of the shafts although such balanced mounting is to be preferred so as to minimize wear on the shaft. The means of mounting the tool rests and wheel guards as shown in Figs. 1, 2 and 4 may likewise be varied without departure from the scope of the invention as may other mechanical features thereof which suggest themselves to one familiar with machine operation.

I have disclosed an apparatus whereby a plurality of grinding wheels of different characteristics may be compactly mounted and may be successively or alternatively brought into engagement with means for causing rotation thereof without necessitating the consumption of a great deal of space or the provision of power sufficient to drive all of the plurality of wheels simultaneously. These objects have been accomplished by the provision of pivotable driving 7 means which may be retracted from a reel supporting a plurality of grinding wheels to permit rotation of the reel so as to station the desired grinding element in operative position. Thereafter the pivotable driving means may be pivoted into engagement with the grinding wheel shaft and locked in this position for the period of desired use. Many modifications may occur to those skilled in the art without departing from the scope of the invention as set forth in the foregoing description and the following claims.

I claim:

1. A grinder comprising a reel rotatably mounted on a supporting stand, a plurality of shafts rotatably mounted to the reel, grinding elements mounted on the respective shafts, and drive means adapted to cause rotation of individual ones of the shafts as the reel is rotated to engage the shafts with the drive means.

2. A grinder comprising a rotatable reel mounted on a supporting stand, a plurality of spaced shafts rotatably mounted to the reel parallel to the axis of rotation of the reel, grinding elements mounted on the respective shafts, drive means adapted to cause rotation of individual ones of the shafts as the reel is rotated to engage the shafts with the drive means.

3. A grinder comprising a rotatable reel her zontally mounted on a supporting stand, four rotatable shafts mounted to the periphery of the reel, and parallel to the axis of rotation thereof, grinding elements mounted on the respective shafts, drive means adapted to cause rotation of individual ones of the shafts as the reel is rotated to engage the shafts with the drive means.

A grinder according to claim 3 wherein the four rotatable shafts mounted to the periphery of the reel are equally spaced around the periphcry of the reel.

5. A grinder comprising a rotatable reel mounted on a supporting stand, a plurality of spaced shafts rotatably mounted to the reel parallel to the axis of rotation of the reel, grinding elements mounted on the respective shafts, a pulley mounted on each shaft so that the pulleys on all of the shafts will lie in a single plane, drive means adapted to cause rotation of individual ones of the shafts by engaging the pulley mounted thereon as the reel is rotated to engage the shafts with the drive means.

6. A grinder comprising a rotatable reel horizontally mounted on a supporting stand, a plurality of spaced shafts rotatably mounted to the reel parallel to the axis of rotation of the reel, grinding elements mounted on the respective shafts. a pulley mounted on each shaft so that all of the pulleys will lie in a vertical plane, drive means adapted to cause rotation of individual ones of the shafts by engaging the pulley mounted thereon as the reel is rotated to engage the shafts with the drive means, and means for locking the drive means to the reel When engaged in powered relationship with one of said shafts.

7. A grinder comprising a rotatable reel horizontally mounted on a supporting stand, a plurality of spaced shafts rotatably mounted through the periphery of the reel, grinding elements mounted on the respective shafts, a pulley mounted on each shaft so that all of the pulleys will lie in a single vertical plane, drive means adapted to cause rotation of individual ones of the shafts by engaging the pulley mounted thereon as the reel is rotated to engage the shafts with the drive means, said drive means comprising a motor driven belt adapted to partially encircle the pulley on the shaft which is in operative engagement therewith.

8. A grinder comprising a rotatable reel horizontally mounted on a supporting stand, a plurality of spaced shafts rotatably mounted through the periphery of the reel, a grinding element mounted near the end of each of the shafts,

a pulley mounted on each shaft so that all of the pulleys Will lie in a single vertical plane, a housing pivotably mounted to the supporting stand and adapted to pivot at right angles to the axis of rotation of the reel, a motor mounted in the lower portion of the pivotable housing, a pulley mounted on and driven by the motor, an idler pulley rotatably mounted in the upper portion of the housing, a belt mounted to said pulley mounted on.the motor and to said idler gear so as to travel continuously thereon, and means for engaging the housing and reel in fixed relationship so as to cause the belt to partially encircle the pulley on one of the shafts.

9. An apparatus according to claim 8 wherein the means of engaging the housing in fixed relationship with the reel comprises a pair of locking arms mounted on a shaft pivotably afiixed .to the housing and shaped so as to grasp projecting bosses formed on the end of the reel and to be held in such position by spring tension, and a lever arm aflixed to said shaft to permit counter force to be applied thereto to raise the locking arms from the bosses.

10. An apparatus according to claim 9 wherein the loclLng shaft is square broached at either end and is adapted to look within notches formed in the periphery of the end members of the reel.

11. An apparatus according to claim 8 wherein the belt consists of a double-A type belt.

12. A grinder comprising a reel rotatably mounted on a supporting stand, a plurality of shafts rotatably mounted to the reel, grinding elements mounted on the respective shafts, drive means adapted to cause rotation of individual ones of the shafts as the reel is rotated to engage the shafts with the drive means, means for pivoting the drive means so as to disengage the drive means from the pulley and means for locking the drive means in association With the pulley.

13. An apparatus according to claim 12 wherein thereel comprises a horizontally rotatable shaft supporting two disc-shaped end members, a plurality of bosses formed on the periphery of each of the end members, the bosses on'each member being in line with corresponding bosses on the opposite member, and the said rotatable shafts being journaled through these bosses.

14. An apparatus according to claim 13 Wherein the end members are webbed to provide additional strength and are provided with means for detachably fixing tool rests and guards thereto in operable relationship with each of the grinding element mounted to the ends of the plurality of shafts.

15. A grinder comprising a rotatable reel rotatably mounted on a supporting stand, a plurality of shafts rotatably mounted to the reel, grinding element mounted near an end of each shaft, and pivotable drive means adapted to be pivoted away from the reel to permit rotation thereof and to be pivoted toward the reel to engage one of said shafts in power transmitting relationship.

16. A grinder according to claim 15 wherein the pivotable drive means com-prises a pivotable housing supporting a motor, a pulley driven by said motor, an idler pulley spaced from said first mentioned pulley and a .belt encircling said' pulleys and adapted to engage one of said shafts when the housing is pivoted against the reel.

WILLIAM O. DENNIS. 

